The present invention relates to apparatus and methods for determining dimensions such as diameter, thickness, aperture size, bore size, and the like and for monitoring object dimension, tool position or tool form. At present, there are many devices for determining dimensions of various objects. For example, in modern industrial applications, it is well known to utilize contact points to transduce a dimension to an electronic transducer. In a typical application at the present time, such contact points would routinely touch the inner diameter of an engine cylinder bore. Linear Voltage Displacement Transducers (LVDT transducers) connected to the contact members, are provided to sense the location of the contact members and thus relate to the bore diameter.
Such electronic transduction systems using contacts have begun steadily replacing the air gages previously used which utilized air back-pressure against a surface of the object as the measuring variable. These air gages have the advantage of no contact between the object and the gage. The reason for the replacement of air gages is the much higher range, stability and maintainability of the electronic sensors which advantages offset the disadvantages caused by use of contact rather than non-contact measurement.
It is an object of the present invention to provide apparatus and methods for determining a dimension of an object and for monitoring object dimension, tool position and tool form in working on an object. It is a further object of the invent ion to provide such apparatus and methods which has advantages over the previously known devices and methods, such as those mentioned above, and which over-come several of the disadvantages thereof.